Allow for encrypted multi-region, cross account use

[fred-vogt-dod]

Build from an outside network (3rd party CI Vendor)

packer build \
  -var-file=al2_x86_64.pkrvars.hcl \
  -var 'eks_version=1.xx' \
  -var 'ssh_interface=public_ip' \
  -var 'temporary_security_group_source_public_ip=true' \
  -var 'aws_region=us-east-1' \
  -var 'subnet_id=subnet-...' \
  -var 'encrypt_boot=true' \
  -var 'region_kms_key_ids={"us-east-1": "arn:aws:kms:us-east-1:<account>:key/<key-id>", "us-west-2": "arn:aws:kms:us-west-2:<account>:key/<key-id>"}' \
  -var 'ami_regions=["us-east-1", "us-west-2"]' \
  -var 'ami_org_arns=["arn:aws:organizations::<account>:organization/<org-id>"]' \
  .

Build from a local system with VPN access

packer build \
  -var-file=al2_x86_64.pkrvars.hcl \
  -var 'eks_version=1.xx' \
  -var 'ssh_interface=private_ip' \
  -var 'aws_region=us-east-1' \
  -var 'subnet_id=subnet-...' \
  -var 'encrypt_boot=true' \
  -var 'region_kms_key_ids={"us-east-1": "arn:aws:kms:us-east-1:<account>:key/<key-id>", "us-west-2": "arn:aws:kms:us-west-2:<account>:key/<key-id>"}' \
  -var 'ami_regions=["us-east-1", "us-west-2"]' \
  -var 'ami_org_arns=["arn:aws:organizations::<account>:organization/<org-id>"]' \
  .